var name = '小明'
var age = 18
var flag = true
function sum(num1,num2) {
  return num1 + num2
}

if (flag){
  console.log(sum(20,30));
}

//导出
//1.导出方式一：
export {
  flag,sum

}

//2.导出方式二：
export  var num1 = 1000;
export  var height = 1.88

//3.导出函数/类
export  function mul(num1,num2) {
  return num1 * num2
}

export class Person{
  run(){
    console.log('在奔跑');
  }
}